1. Field of the Invention
The present invention relates to a cleaning jig, and more particularly, to a cleaning jig for cleaning a liquid crystal container.
2. Discussion of the Related Art
Generally, recent developments in the field of communications have increased the demand for various types of display devices. In response to this increased demand, numerous types of flat panel displays (e.g., liquid crystal displays (LCDs), plasma display panels (PDPs), electro-luminescent displays (ELDs), vacuum fluorescent displays (VFDs), etc.) have been developed.
Owing to their high resolution, light weight, thin profile, and low power consumption, LCD devices have been widely used in mobile devices (e.g., monitors of notebook computers) as well as televisions and computer monitors.
LCD devices generally include two substrates coupled to each other and separated by injected liquid crystal material. Liquid crystal materials exhibit mid-range and long-range molecular orders. Liquid crystal materials exhibit a mid-range molecular order upon melting (i.e., transitioning from a solid phase to a liquid phase), in that the liquid crystal material can assume a phase that is neither solid nor liquid. Accordingly, liquid crystals may exhibit properties of both liquids and crystals, within predetermined temperature ranges. Liquid crystal materials exhibit optical birefringence properties of optical anisotropic crystals when they are irradiated with light or when electric or magnetic fields are applied to them.
LCD devices are manufactured using a series of processes including array formation process, color filter formation process, liquid crystal (LC) cell formation process, and module formation process.
The array formation process includes steps of deposition, photolithography, and etching to form an array of thin film transistors (TFTs) on a first substrate. The color filter formation process includes the formation of a black matrix to shield light from being transmitted through a region, other than a pixel region, in a second substrate. The color filter formation process further includes steps of forming red (R), green (G), and blue (B) filters over the entire surface of the second substrate, and forming a common electrode made of ITO (Indium Tin Oxide) on the color filters.
The LC cell formation process includes steps of forming an LCD cell by bonding the first substrate, on which the array of TFTs are formed, to the second substrate, on which the black matrix, color filters, and common electrode are formed. The bonded substrates are spaced apart a uniform distance by a cell gap. The LC cell formation process further includes injecting liquid crystal material into the cell gap.
The module formation process includes the steps of manufacturing an LCD module by providing a circuit for signal processing, electrically connecting an LCD panel with the circuit via mounting technologies, and assembling other components.
A typical LC cell formation process will now be described in greater detail.
A first cassette (not shown), housing a first plurality of first substrates, and a second cassette (not shown), housing a second plurality of second substrates, are mounted into respective ports via loaders.
Each of the first and second substrates are designed to be used in the manufacture of at least one LCD panel. A plurality of gate lines are formed at fixed intervals along a first direction on the first substrate and a plurality of data lines are formed along a second direction on the first substrate, perpendicular to the first direction. Accordingly, a plurality of pixel regions may be formed in a matrix pattern at the crossing of each of the gate and data lines. A plurality of pixel electrodes are formed at the pixel regions and a plurality of thin film transistors (TFTs). In order to prevent light leakage in regions outside the pixel regions, a black matrix layer, color filters, and common electrode are sequentially formed on the second substrate.
Next, the first substrate and the second substrate are selected from the first and second cassettes, respectively, via a robot arm that is programmed to select each of the first substrates and the second substrates one at a time.
Referring to FIG. 1, an orientation film formation process (1S) is performed wherein orientation films are deposited on each of the selected first and second substrates. The orientation films uniformly align the liquid crystal material within the cell gap. Particularly, the orientation film process (1S) is carried out by pre-cleaning each of the substrates, printing the orientation films, plasticizing the orientation films, inspecting the orientation films, and rubbing the orientation films.
After the orientation film process (1S) is completed, a gap formation process is then performed. During the gap formation process, the first and second substrates are cleaned (2S), spacers are dispensed on the first substrate so as to ensure the cell gap is uniform (3S), sealant is dispensed on the second substrate and a liquid crystal injection inlet is formed at an edge portion of each panel (4S), and the first and second substrates are pressed and bonded together (5S).
The bonded first and second substrates are then cut and processed into an LCD panel (6S).
Subsequently, liquid crystal material is injected through the liquid crystal injection inlet into the cell gap of each of the LCD panels and the liquid crystal injection inlet is then sealed (7S).
Lastly, cut surfaces of the first and second substrates are then polished, and the LCD panel is then inspected for appearance and electrical failure (8S).
The liquid crystal injection process will now be described in greater detail.
In injecting liquid crystal material, liquid crystal material is provided in a liquid crystal container, the liquid crystal container is loaded into a vacuum chamber, and pressure in the vacuum chamber is reduced, thereby creating a vacuum within the vacuum chamber so that any moisture adhered to the inner surface of the liquid crystal container or any air bubbles in the liquid crystal material are removed.
While maintaining the vacuum within the vacuum chamber, the liquid crystal injection inlet of an empty LC cell contacts, or is dipped into, the liquid crystal material in the liquid crystal container. The pressure of the vacuum chamber is then increased and, due to the pressure difference between the interior of the empty LC cell and the interior of the vacuum chamber, liquid crystal material is injected through the liquid crystal injection inlet into the cell gap.
There are, however, disadvantages to manufacturing LCD devices according to the above liquid crystal injection method.
First, the aforementioned liquid crystal injection method is a time consuming process. By performing the steps of cutting substrates into LCD panels, maintaining a vacuum within cell gap of the LCD panels, contacting the liquid crystal injection inlet with liquid crystal material, injecting liquid crystal material, a considerable amount of time is required to perform and the productivity of the process is thus reduced.
Secondly, as LCD panels get larger, liquid crystal material may not be completely injected into the cell gap.
Thirdly, the aforementioned injection process is very complex and a wide variety of considerably large injection apparatuses are required.